Body fat distribution and the distribution and the distribution of scientific knowledge

The Importance of the Quantity and the Distribution Assessment of Fat Tissue in a Diagnosis of Insulin Resistance

BACKGROUND

Accurate human body composition assessment is becoming very important in clinical practice due to the possibility of early diagnosis and preventive interventions of metabolic disorders. Fats are one of the most important elements in maintaining normal body structure and different methods are used to determine its total amount and distribution. The amount and distribution of abdominal white adipose tissue, and especially the visceral type, provides important parameters in the development assessment of central obesity, insulin resistance, diabetes and other chronic non-infectious diseases.

OBJECTIVE

The aim of the study was to determine the amount of visceral adipose tissue in adults who are overweight and then estimate the probability of developing insulin resistance (IR) in those with higher amounts of visceral adipose tissue. Based on a comparison of the amount of visceral adipose tissue and the frequency of IR, evaluate the clinical significance of a routine procedure for body structure assessment in relation to the amount of visceral adipose tissue.

METHODS

Subjects were adults of both sexes aged 20 to 77 years, who were patients in two family medicine clinics. Including criteria for the study were: increased body weight (BMI≥25) and normal blood glucose values (4.0 - 5.4 mmol/L). All subjects underwent anthropometric measurements (BMI, waist circumference, waist-hip ratio) and body structure assessment with bioelectrical impedance. According to the values for the amount of visceral adipose tissue (below and above 110 cm2), the subjects were divided into two groups. All subjects underwent an IR test. We used the HOMA 1 value of 2 as a cut off for the risk of chronic non- infectious diseases in non-diabetic population.

RESULTS

The study included 80 patients. 14 patients did not complete the study, so the total number of subjects was 66 (39 women and 27 men). 36 subjects had elevated values of visceral adipose tissue (over 110 cm2). In this group, the presence of IR was registered in 30 patients or 81%. In the control group with a normal amount of visceral adipose tissue, IR was registered in 10 subjects or 33%, which is a statistically significant difference.

CONCLUSION

Increased amount of visceral adipose tissue in overweight patients significantly affects the occurrence of IR. For the patients with an increased amount of visceral adipose tissue, it is necessary to introduce intensive preventive measures to stop the development of diabetes and other complications as a result of IR presence.

History of Nonalcoholic Fatty Liver Disease

Based on the assumption that characterizing the history of a disease will help in improving practice while offering a clue to research, this article aims at reviewing the history of nonalcoholic fatty liver disease (NAFLD) in adults and children. To this end, we address the history of NAFLD histopathology, which begins in 1980 with Ludwig's seminal studies, although previous studies date back to the 19th century. Moreover, the principal milestones in the definition of genetic NAFLD are summarized. Next, a specific account is given of the evolution, over time, of our understanding of the association of NAFLD with metabolic syndrome, spanning from the outdated concept of "NAFLD as a manifestation of the Metabolic Syndrome", to the more appropriate consideration that NAFLD has, with metabolic syndrome, a mutual and bi-directional relationship. In addition, we also report on the evolution from first intuitions to more recent studies, supporting NAFLD as an independent risk factor for cardiovascular disease. This association probably has deep roots, going back to ancient Middle Eastern cultures, wherein the liver had a significance similar to that which the heart holds in contemporary society. Conversely, the notions that NAFLD is a forerunner of hepatocellular carcinoma and extra-hepatic cancers is definitely more modern. Interestingly, guidelines issued by hepatological societies have lagged behind the identification of NAFLD by decades. A comparative analysis of these documents defines both shared attitudes (e.g., ultrasonography and lifestyle changes as the first approaches) and diverging key points (e.g., the threshold of alcohol consumption, screening methods, optimal non-invasive assessment of liver fibrosis and drug treatment options). Finally, the principal historical steps in the general, cellular and molecular pathogenesis of NAFLD are reviewed. We conclude that an in-depth understanding of the history of the disease permits us to better comprehend the disease itself, as well as to anticipate the lines of development of future NAFLD research.

Rosiglitazone-Mediated Effects on Skeletal Muscle Gene Expression Correlate with Improvements in Insulin Sensitivity in Individuals with HIV-Insulin Resistance

Rosiglitazone, an agonist of peroxisome proliferator activated receptor (PPARγ), improves insulin sensitivity by increasing insulin-stimulated glucose uptake into muscle tissue. This study was undertaken to assess changes in expression of PPAR-regulated genes in muscle tissue following treatment of HIV-associated insulin resistance with rosiglitazone. Muscle gene expression was assessed in twenty-two seronegative HIV subjects (control), 21 HIV-infected individuals with normal insulin sensitivity (HIV-IS) and 19 HIV-infected individuals with insulin resistance (HIV-IR). A subset of the HIV-IR group (N=10) were re-evaluated 12 weeks after treatment with 8 mg/d of rosiglitazone. The HIV-IR group's rosiglitazone-mediated improvement in insulin sensitivity was highly correlated with increased expression of PPARγ and carnitine palmitoyl transferase-1 (CPT-1), (r=0.87, P<.001) and (r=0.95, P<.001), respectively. The changes in PPARγ expression were also correlated with the changes in CPT1 expression (r=0.75, P=.009). The results suggest that rosiglitazone; may have a direct effect on muscle tissue to improve insulin sensitivity.